Glutamine Synthetase Expression Technology

Glutamine Synthetase Expression Technology Principle

The Glutamine Synthetase Expression Technology is widely used for recombinant antibody and protein production in mammalian cell culture. Glutamine Synthetase Expression Technology relies on glutamine synthetase enzyme which synthesizes glutamine from glutamate and ammonium ions. Since many mammalian cells cannot make endogenous glutamine, transfection of such cells with a vector encoding Glutamine Synthetase enzyme ensures cell survival in culture. And for those cells that make endogenous glutamine, using the Glutamine Synthetase enzyme inhibitor, methionine sulfoximine (MSX), enables suppression of the endogenous glutamine. In such an event the engineered Glutamine Synthetase activity is useful in cell survival and for driving recombinant gene expression.

Figure 1: Glutamine Synthetase Technology Principle

Advantages of GenScript CHO Glutamine Synthetase Technology

While there are several advantages to the use of CHO Glutamine Synthetase technology, the 3 most important attributes would be Productivity, Speed and Stability.

GenScript CHO Glutamine Synthetase Technology Productivity

Use of GenScript Glutamine Synthetase technology will ensure the establishment of economic processes. GenScript CHO Glutamine Synthetase technology reliably results in high yielding cell lines. While the maximum expression levels attainable depend on the product, GenScript has created cell lines producing >5g/L rAb with production rates in the range of 50-100 pcd.

GenScript CHO Glutamine Synthetase Technology Speed

Cell line development speed is crucial to overall project success. GenScript CHO-Glutamine Synthetase technology allows for rapid selection of high yielding cell lines during the first screen. Even higher yields are achieved through media and process optimization. This significantly reduces the time required to generate a cell line suitable for GMP process. Also, since the GenScript CHO-Glutamine Synthetase cell line is pre-adapted to growth in chemically defined, animal free media and suspension culture, it aids adaptation of the cell line back to growth in suspension culture after transfection.

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Figure 5: Gram-level mAb productivity is achievable in 14-17 weeks

GenScript CHO Glutamine Synthetase Technology Stability

CHO Glutamine Synthetase cell lines that are stable in terms of product concentration, growth and product characteristics are created using GenScript CHO Glutamine Synthetase technology.

GenScript CHO Glutamine Synthetase Technology Summary

The ultimate goal of cell line development is to obtain clonal cell lines that produce the desired protein or recombinant antibody (rAb) with high specific productivity, at consistently high levels, over an extended number of generations, allowing for scalable and cost-effective processes. GenScript CHO Glutamine Synthetase Technology can help realize this goal. For details on the GenScript CHO Glutamine Synthetase service click here.

For details on GenScript's overall stable cell line service portfolio, click here.